Mechanical stoker



Dec. 3, 1935. J. B. M acKENZlE MECHANICAL STOKER Filed 001;. 9, 1928 2Sheets-Sheet 1 m In W ii I I W WW mwm Dec.3, 1935. JBMMKENZIE 2,022,994

MECHANICAL STOKER Filed Oct. 9, 1928 2 Sheets-Sheet 2 of the tender, bybolts i1 Patented Dec." 3, 1935 PATENT "OFFICE MECHANICAL STOKER JosephB. MacKenzie, Aspinwall, Pa.,

mesne assignments, to

assignor, by The Standard Stoker Company, Incorporated, a corporation ofDelaware Application October 9, 1028, Serial No. 311,304 16 Claims. (01.-101 The invention relates to an appliance for feeding fuel to steamboilers, and is herein described as applied to locomotive boilers,although its ap- Dlication is not limited to that type of boiler.

The objects of this invention are, to make a stoker that will feedthrough the fire-door opening of a boiler without necessitating a changein size, design or location of the fire door: to make a compact designand one that will take up very -little room in the locomotive cab, whichis already very crowded: to provide a stoker design, for locomotives,that can be used with a stationary trough in the tender: to furnish astoker of simple construction with few movable parts, and these partseasily accessible.

The improvements claimed are hereinafter fully set forth.

In the accompanying drawings:

Figure 1 is a sectional view of the rear of the boiler and the front ofthe tender and stoker, on line i-l of Figure 4;

Figure 2 is a sectional view, taken through the fire-door opening online 2-2 of Figure 1, showing the distributing plate which passesthrough the fire-door opening;

Figure 3 is a sectional view, taken on line 38 of Figure 1, showing thetender conveyor and central portion of the locomotive tender;

Figure 4 is a. plan view showing the stoker and driving engine with thefire-door box and guideplate removed;

Figure 5 is a rear view of the part of the stoker adjacent to thefire-door opening.

In Figure 1 a conveyor trough, I, is shown located below the coal space,2, of the locomotive tender. An intermediate trough, 3, connects conveyor trough i with elevating conduit 4, rigidly mounted on thelocomotive, and is flexibly con-- nected at 5 and 6 to the conveyingtrough and the elevating conduit respectively.

A helical conveyor screw, 1, is connected by universal joint 8 tointermediate screw 8.

Flexible connection 5 and universal joint 8 are to allow movementbetween the tender conveyor and intermediate trough. Flexible connection6 is to allow movement between the intermediate trough and elevatingconduit.

Intermediate conduit 3 is made in two pieces, l8 and I5; the forwardpiece, l5, moves .in and out in rear piece ill to allow for longitudinalmovement between locomotive and tender.

Conveyor trough l is bolted to the floor, i6,

shown in Figure 3. Slide plates l8, of the type generally used, are

ing plate 3| movable on angles i9 and 20, which are mounted on the sidesof the conveyor trough.

Transverse angles 2| form a connection between vertical angles 22 and 23which support the tender deck. The transverse angles also 8 serve asstiffening members for the vertical anles.

Run-of-mine coal falls from the coal compartment, 2, through slide-plateopening 24 into the conveying trough and is carried forward by conveyorscrew 1 through crusher 25, where the large lumps of coal are crushed toa size suitable for economic firing, to intermediate trough 3. Screw 8conveys coal through intermediate trough to elevating conduit 4 anddelivers it to screw 38 which, in turn, elevates it to distributin thefire-door opening.

The intermediate casing is provided at its front end with a pinconnection, 32, which is located at its top, due to the fact that theend, 88, is

cut oil at a slant corresponding approximately to this type of flexiblepin connection allows for a considerably longer intermediate conduitthan 30 if a ball connection was. used on the frontend. The lower part4| of the elevating unit is provided with a conduit receiving portion 88having a substantially cylindrically shaped inside surface 81 arrangedto receive a longitudinally convex enlargement 88 on the front end ofthe for-- ward intermediate section J8. The pin 82 extends through thereceiving portion 88 of the lower part 4i and a hole 88 in the convexenlarged end 88 of the forward intermediate section I8, and has ashoulder 98 to prevent it from passing through the hole and disengagingthe conduits. The hole 88 is smaller in diameter at the middle than atthe inner and outer surface of the convex enlarged end 88 of the forward45 intermediate section, which provides clearance is made in two pieces,40 and 4|.

of the elevating conduit. A sealing device. 39, located in the bottom ofthe elevating conduit, prevents coal from getting into the worm-wheelcase.

In stokers of this type it is general practice to support the stokerfrom the mud-ring of the boiler. In rthis case, however, the elevatingunit The lower piece, M, is supported on the locomotive frame by abracket, 42, and the upper piece, 40, is attached by means of flanges 43and 44 to a filler piece, 45, which is, in turn, attached to thelocomotive back-head adjacent -to the fire-door opening. The partcarried on the frame is the heavier part, and by this method the weightcarried by the boiler has been considerably diminished.

In order to allow for boiler expansion and the movement of the frame thelower section of the elevating conduit is provided at its top with aring, 46, which is held. firmly against its upper surface by springs 41.This ring is slidable on the upper surface of the lowersection. Theupper part of the elevating conduit fits inside this ring at 48 and isslidable therein.

It has been found on many locomotives that, when backing up against along train in order to take up slack between the cars, the frame work isdeflected upward. This movement of the frame and the expansion of theboiler are allowed for in the action of this ring on the top of thelower part of the elevator casing and its sliding on the outside of theupper part of the easing respectively.

The elevating screw is mounted loosely on the end of the driving shaftat 49, and the clearance between the screw flight and the conduitsection 40 allows for lateral movement between the upper and lowerportions of the elevating conduit.

In applying the stoker the lower portion of the elevating'conduit islocated on the frame so that the rearward face of the screw touches therearward wall of the upper part of the conduit. when the boiler expandsand the upper portion moves backwards the screw will lie with itsforward face against the forward wall of the upper conduit. The view inFigure 1 shows the location of the screw and the conduit when the boileris hot and fully expanded.

The upper end, 50, of the elevating conduit, 4, changes from a round toa rectangular section, keeping the same area as in the circular part ofthe conduit. The longest sides of the rectangular outlet'opening at the'top of the elevating conduit, 4 are disposed transversely of thelocomotive. This change in the section of .the elevating conduit is madeto allow the upper edge of the conduit to come closer to the' back-headof the boiler than has hitherto been possible. This constructiondecreases the distance that {he fire-door, 5|, must be moved from thebackead.

The fire-door box or casing, 52, is attached to the filler piece, 45, byflange 53, and to the elevating conduit section or feed tube 40 byflanges 54 and 55. The fire-door, 5|, is supported on the fire-door box,52, and rests on the lower edge in groove 56 on the upper part of theelevating conduit section 40.

The fire-door box, 52, provides a compartment, adjacent and exterior tothe fire-door opening, into which the coal is delivered directly fromthe elevating screw: the box further provides a means for locating thefire-door back beyond-the point of elevation of the fuel.

It will be seen this box or casing has an open bottom mounted over theopen top of the conduit section 4|]. Preferably, the top and side wallsof .ward of the firebox wall and in a level below the 1 highest pointalong the bottom of the firing opening. The distributor plate 3| beginswhere the front wall ends and constitutes an extension thereof into thefiring opening. As best shown in Fig. l, the rear and side walls of theconduit section 49 terminate in the same plane above the level of theupper edge of the front wall and the central portion of the distributorplate 3!. This construction aids in. advancing the fuel as soon aspossible into the firing opening.

Taperlng the elevating screw, the conduit section 40 and the box orcasing permits the firedoor to be located much nearer the backhead thanwould otherwise be possible.

If a straight elevator conduit were employed 2:; and the liredoorcorrespondingly moved back to suit, difficulty would be experienced inobtaining access to the firebox. With the construction disclosed thefiredoor is so located that access to the firebox is not hindered.

Another advantage of the peculiar shape of the elevating conduit as awhole at its top portion is the fact that the coal is moving upward andinto the fire-box at practically the entire width of the fire-door andthus a broad bank of coal is made to pass across the plate and fall infront of the distributing jets. This results in there being no dead coalspace in the top of the elevator to accumulate coal where it would cokeand stick fast to the firing plate. The fact that the 3 upper end of theconduit section 40 is the whole width of the fire-door opening and thefire-door causes a forward moving stratum of coal to pass across thedistributing plate at all times.

Guide-plate 51 is mounted in the fire-door box'; and supported bytrunnions 58 and 59 in the sides of the box. This plate is located justabove the end of the elevating screw, and is for directing the coaltoward the distributing 'plate, thus preventing the coal from beingforced upward into 5 the fire-door box.

Another purpose of the guide-plate, 51, is to prevent the coal frompiling up high enough to fall out of the fire-door should it be openedwhile the stoker is in operation.

The guide-plate, 51, is provided with a rod, 80. and crank mechanism,6|, which is fastened to the worm-shaft, 62, to give a backward andforward or oscillatory motion which has the effect of pushing the coalforward on to the distribut- 60 ing portion of the plate.

It will be noted that the guide-plate, 51, can be readily turned out ofthe .way or can be dropped flush to provide for hand firing, thusleaving an unrestricted fire-door opening. This is accomplished byremoving pin 63 and swinging plate by means of arm 64.

Distributing plate 3| is attached to the elevating casing at 65 andrests on the'lower surface of the fire-door opening on supporting ribs66. These ribs keep the main body of the plate slightly above the lowersurface of the fire-door opening and allow space for air to enter underthe distributing plate, thus affording a cooling means to prevent theplate from becoming over- 7 2,022,994 heated. The outer edges 61 and 68and the cen-,-

tral portion of the distributing plate are shaped to conform to thecontour of the fire-door opening. This creates in longitudinal sectionan archlike formation of the plate over that portion of the firebox wallforming the lower extremity of the firing opening.

In the outer edges of the distributing plates are cored passages 69 andIll communicating with cored passages H and 12 in the front of theplate. These passages are for applying fluid pressure to distributingjet holes 13 in the front face of the distributing plate. Pipes 14 and Iadmit the fluid pressure into the above mentioned cavities.

The pressure in the separate jet cavities is governed manually by meansof valves in these pipes. The jet holes leading into cavity lldistribute the coal to the right-hand side of-the grate and, into cavity12, to the left-hand side.

Providing these two cavities gives the fireman separate control overeach half of the fire and,

by using more or less pressure, coal can be distributed to the front orback as he wishes.

As the coal is delivered from the end of the elevationg screw it ischanged in its direction of fiow by the guide-plate, which deflects itinward onto the rear of the distributing plate from where it is pushedforward by the oncoming coal to the distributing table, I6, which liesin front of and below the distributing jets, and is here shown integralwith the distributing plate: this construction, however, .is notnecessary. The pressure required to force the coal to the distributingtable is somewhat diminished, however,

due to the fact that the distributing plate slopes downward at itsforward end and the coal will have a tendency to slide forward to thedistributingtable due to the force of gravity and the vibration of thelocomotive.

The driving engine, 11, is shown mounted on' the locomotive frame anddrives the elevating unit through aflexible drive-shaft, 18, thedriveshaft being driven from the motor through a bevel gear reduction,19, these gears, in turn, being driven by worm and worm-wheel reductionenclosed in casing 80. The shaft and driving engine are both placed onthe left hand side of the locomotive to enable the engine and worm gearcasing to be cast integral.

The conveyor drive-shaft, 8|, driving the conveyor trough from the rear,is connected to the worm wheel reduction at 82. This form ofconstruction eliminates thenecessity of a long intermediate shaft andhousing between the driving engine and worm wheel case, which would benecessary if they were cast separately and located on opposite sides ofthe locomotive. This engine mounting and drive organization has beenmade the subject matter of a divisional application, Serial No. 722,087,filed April 24, 1934.

The cored passage, 83, extends along the upper rearward portion of theelevating conduit and communicates with jet holes 84. Fluid pressure isadmitted through the cored passage to the jet holes. The jet holesextend inwardly and upwardly and are for removing the coal from abovethe elevating screw, thus allowing the fireman to lower the guide plate,51, in order to have free access to the fire-door opening.

In ordinary running condition it is not necessary to use these jets, butwhen the stoker is stopped coal still lies between the guide-plate andthe upper part of the elevator screw. With this condition it will beimpossible to lower the guide-plate, but by using these jets this massof coal is removed and leaves a free space into which the guide-platemay be dropped.

From the foregoing description it can be seen that a stoker of novelconstruction has been de- 5 vised which takes up much less room in thefiredoor opening and in the locomotive cab than many of the existingdesigns, and is easily applicable to all locomotives.

I claim as my invention:

1. In combination with a locomotive having a firebox provided with abackhead having the conventional substantially oval shaped hand firingopening therein, a stoker conduit positioned exterior of the firebox andhaving a conveyor 15 screw therein delivering fuel to the lower portionof said opening, a distributor plate extending forward from the upperend of said conduit into said opening and conforming substantially tothe shape of the lower edge of said opening, the sides of said platecurving upwardly to prevent fuel contacting with the sides of saidopening, said plate being formed with passages in said side portions andwith communicating transverse passages in its forward end portion hingedplate at the upper end of said conduit for moving the fuel dischargedupward by said screw forward to said means, said plate being mounted atits lower end on. a fixed axis extending transversely and rearward ofthe upper extended axis 40 of said-- screw, power transmitting meansoperatively connected. with said screw at the base of said conduitcomprising gearing and a rotatable shaft, and means operativelyconnecting said hinged plate with said shaft for'oscillating same. 3. Incombination with a locomotive having a firebox provided with a backheadhaving the conventional hand firing opening therein, a stoker conduitmounted exteriorly of the firebox and arranged to deliver fuelto thelower portion of 60 said opening, and a distributor plate extendingforward from theupper end of said conduit into and conformingsubstantially to the shape of the lower marginal portion of the openingand having side portions extending upwardly therein,

said plate being formed with passages in said side portions and withcommunicating transverse passages in its forward end portion and havingjet openings communicating with the transverse passages arranged toissue pressure fluid jets forward of the upper end of said conduit. i

4. In combination with a locomotive having a firebox provided with" abackhead having a firing opening therein, a stoker conduit mountedexterior of the firebox and arranged to deliver fuel to the lowerportion of said opening, a distributorplate extending forward from theupper end of said conduit into said opening, said plate having side.portions extending upwardly adjacent the sides of the firing opening toprevent fuel contactlng with the sides of said opening, and said platebeing formed with a passage in at least one of said side portions andwith a communicating transverse passage in its forward end portion andtransverse passage arranged to issue fluid jets for-discharging fuelinto the firebox.

5. In combination with a locomotive having a firebox provided with abackhead having a firing opening, an upright stoker conduit arrangedcentrally of the backhead exterior of the firebox, a conveyor screwwithin said conduit for deliv ering fuel to the lower portion of saidopening, a chambered member at the lower portion of the firing openinghaving jet openings forward of the upper end of said conduit, a hingedplate at the upper end of said conduit, said plate being mounted at itslower end on an axis extending transversely and rearward of the upperextended axis of said screw, and means for oscillating said plate.

6. In combination with a locomotive having a firebox provided with abackhead having a firing opening, an upright stoker conduit arrangedcentrally of the backhead exterior of the firebox, a conveyor screwwithin said conduit for delivering fuel to the lower portion of saidopening, a chambered member at the lower portion of the firing openinghaving jet openings forward of the upper end of said conduit for issuingfuel scattering pressure fluid jets; an inclined hinged plate attheupper end of said conduit, said plate being mounted at its lower end ona fixed axis .extending transversely and rearward of the upper extendedaxis of said screw, said plate being spaced from said screw 2. distancesufficient to permit the fuel delivered by said screw to pass to saidjets, and means rearward of the upper end of said screw arranged toissue a pressure fluid blast for discharging fuel from the space betweensaid screw and saidplate.

7. In a locomotive having a frame and a firebox provided with abackhead, a stoker conduit disposed more nearly veitical than horizontalmounted adjacent the backhead and arranged to deliver fuel tosaidfirebox, said conduit comprising a lower section attached rigidly to theframe of the locomotive and an upper section secured rigidly with thebackhead, a screw extending within both of said sections for deliveringfuel therethrough, said, screw being mounted in said lower section on afixed axis and arranged in the upper section to provide a space betweenthe edge of the flight of the screw and the inside surface of the uppersection sufficient to permit the upper section to move with the backheadlongitudinally with respect to said frame and laterally in respect tosaid screw when the backhead expands and contracts from the heat in thefirebox.

8. In a locomotive having a frame and a firebox provided with abackhead, a stoker conduit disposed more nearly vertical than horizontalmounted adjacent the backhead and arranged to deliver fuel to saidfirebox, said conduit comprising a lower section attached rigidly to theframe of the locomotive and an upper section secured rigidly with thebackhead whereby the upper section will move laterally with respect tothe lower section when the backhead moves longitudinally on said framedue to expansion and contraction from the heat in the firebox, and asealing member at the juncture of said sections movable with the uppersection and slidably engaging the lower section. I 9. In combination, afirebox having an upstanding wall provided with a firing openingtherein, a stoker conduit mounted exteriorly of the firebox and arrangedto deliver fuel to the inside surface of the aforesaid firebox wall,transverse passages in the forward portion of said plate, said facebeing provided with a plurality of jet holes communicating with saidtransverse passages and said side portions each having a.

passage communicating with one of said transverse passages, and adistributing table within the firebox extending forwardly from said facebelow the jet holes therein.

10. In combination, a firebox having an upstanding wall provided with afiring opening therein, a stoker conduit mounted exteriorly of thefirebox and arranged to deliver fuel to the lower portion of saidopening, a plate-like distributor member extending forward from theupper end of said conduit into said firing opening and conformingsubstantially both in transverse and longitudinal sections tothe shapeof the lower edge of said opening, said plate member having upwardlyextending side portions within the opening and including a transversefront face directed inwardly of the firebox adjacent the inside surfaceof the aforesaid firebox wall. said face being provided with a pluralityof jet holes and said side portions each having a passage and meansproviding communication between each 3 passage and certain of said jetholes, and a distributing table within the firebox extending forwardlyfrom said face below the jet holes therein I and in a level below thehighest point on the surface of that portion of the firebox walldefining the lower extremity of the firing opening considered on thevertical medial plane-of said firing opening longitudinally of thefirebox.

11. In combination, a firebox having an upstanding wall provided with afiring opening 5 therein, a stoker conduit mounted exteriorly of thefirebox and extending from a point below upwardly to said firing openingand arranged to deliver fuel thereto, said conduit having a front wallthe centrally disposed fuel supporting surface of which at its upperedge terminates rearward of the firebox-wall and below the highest pointon the surface of that portion of the firebox wall defining the lowerextremity of the firing opening considered on the vertical medial planeof said firing opening longitudinally of the firebox, a distributormember extending upwardly,

from said upper edge of the front wall and forwardly into the firingopening closely adjacent the aforesaid lower marginal edge thereof andthence sloping downwardly and inwardly toward the inside of the firebox,said distributor member constituting a fuel supporting extension of saidfront wall and having a transverse front face adjacent the inside suraceof the firebox wall pro- 55 vided with a plurality of jet openings, saiddistributor member including a passage communieating with said jet holesand having an opening directed exteriorly of the firebox for theintroduction of pressure fluid, and adistributing table within thefirebox extending forwardly from said face below said jet holes and in alevel below said highest point in the surface of that portion of thefirebox wall defining the lower extremity of the firing opening.

12. In a stoking apparatus, the combination with a firebox having anupstanding wall with a firing opening therein, a door casing connectedto said upstanding wall having top and side walls surroundingcorresponding portions of the firing opening, a door movably mounted onsaid casing, said door being disposed in spaced relation to said fireboxwall and forming arear wall portion of the casing, a conduit fordelivering fuel upwardly through the lower portion of the casing to saidfiring opening, said conduit having front, rear and side walls, the rearand side walls terminating in substantially the same plane in a levelabove the upper edge of the front fall, said side walls having portionsdisposed in abutting relation to the side walls of the casing, said doorconstituting a continuation of the rear wall of the conduit, and adistributor member disposed in said firing opening at the upper end ofsaid front wall of the conduit, said distributor member having a portionof its upper surface centrally of the firing opening positioned belowthe level of the aforesaid terminal plane of the rear and side walls ofthe conduit.

13. In a stoking apparatus, the combination with a firebox having anupstanding wall with a firing opening therein, a door casing connectedto said upstanding wall having top and side walls surroundingcorresponding portions of the firing opening, a door movably mounted on.said casing, said door being disposed in spaced relation to saidfirebox wall and forming a rear wall portion of the casing, a conduitfor delivering fuel upwardly through the lower portion of the casing tosaid firing opening, said conduit having front, rear and side walls, therear and side walls terminating in substantially the same plane in alevel above the upper edge of the front wall, said side walls havingportions disposed in abutting relation to the side walls of the casing,the said door of the casing constituting a continuation of the rear wallof the conduit, said front wall of the conduit terminating rearward ofthe firebox wall, and a distributor member extending upwardly from theupper edge of said front wall and curving forwardly into the firingopening, said distributor member constituting an extension of said frontwall and having a portion of its upper surface centrally of the firingopening positioned in a level below the aforesaid terminal plane of therear and side walls of the conduit.

14. In a stoking apparatus, the combination with a firebox having anupstanding wall with a firing opening therein, a door casing connectedto said upstanding wall having top and side walls surroundingcorresponding portions of the firing opening, a door movably mounted onsaid casing, said door being disposed in spaced relation to said fireboxwall and forming a rear wall portion of the casing, a conduit fordelivering fuel upwardly through the lower portion of the casing to saidfiring opening, said conduit having front, rear and side walls, the rearand side walls terminating above the level of the upper edge of thefront wall and said side walls having portions disposed in abuttingrelation to the side walls of the casing, said door constituting acontinuation of the rear wall of the conduit and said front wall of theconduit terminating rearward of the firebox wall, and a distributormember extending upwardly from the upper edge of said front wall andcurving forwardly into the firing and a casing disposed above and havingan open 1 bottom in communication with the open top of said feed tube,said casing being connected to the firebox wall and having top and sidewalls surrounding corresponding portions of the firing opening, theplane of the outer marginal edges of said top and side walls beingspaced from the firebox wall and inclined downwardly and rearwardly fromsaid wall in the general plane of the inclined feed tube which isinclined forward and upward from a point below the firing opening, saidfeed tube having front, rear and side walls, the front wall at its upperend terminating adjacent the lower marginal portion of the firingopening and rearward of the firebox wall and the rear wall terminatingin a plane above the upper edge .of said front wall, the side walls ofsaid casing constituting laterally spreading continuations of the sidewalls of said feed tube and the said outer edges of the top and sidewalls of the casing and the upper edge of said rear wall of the feedtube defining an opening in said casing in substantial register withsaid firing opening, a movable door forming a closure for the opening insaid casing and constituting a continuation of the rear wall of the feedtube, and a distributor member extending upwardly from the upper edge ofsaid front wall of the conduit and curving forwardly into the firingopening, said distributor member constituting an extension of said frontwall of the conduit and having a portion of its upper surface centrallyof the firing opening positioned in a level below the upper edge ofthe-rear wall of the conduit.

16. In combination, a firebox having an upstanding wall provided with afiring opening therein, stoker conduit means mounted exteriorly of thefirebox and extending from a point below upwardly to said firing openingand arranged to deliver fuel thereto, said conduit means having a wallthe central fuel supporting surface of which extends to the firebox walland which conduit wall at a point below the highest point on the surfaceof that portion of the firebox wall defining the lower extremity of thefiring opening considered on the vertical medial plane of said firingopening longitudinally of the firebox then slopes forwardly and upwardlyinto said firing opening closely adjacent the aforesaid lower extremitythereof and thence sloping downwardiy and inwardly toward the inside ofthe firebox, and means at the end of the aforesaid downwardly andinwardly sloping portion of said conduit wall for propelling the fuelover the firebed of the firebox including forwardly directed jet holesdisposed infa level below the highest point of the central portion ofthat part of said conduit wall within the firing opening, and adistributor table positioned below the level of said jet holes.

JOSEPH B. MACKENZIE.

